Ocean Acidifi-WHAT?!

As I continue to speak around the country, I frequently ask if those in the audience who have heard of ocean acidification will kindly raise their hands. Sometimes a few do. More often I get blank stares. I’ve been writing about this subject for as long as I’ve been blogging. Longer if you count Senate memos and grad school projects over much of the past decade. Acidification is a huge deal. It’s as serious as climate change, which–despite Mr. Morano’s sorry efforts at special interest propaganda–is indeed a very real threat to biodiversity. Humans included.

So time for another post on what ocean acidification is, how it affects our world, and why this matters. It needs to become prominent on the national radar and a priority in policy discussions. I intend to keep blogging about it until more hands go up in the room. With that, another edition of:

Ocean Acidification 101

Most of us are aware that we’ve been adding lots of CO2 to the atmosphere from the combustion of fossil fuels, land-use changes, and more. But carbon dioxide is also absorbed in oceans and taken up by terrestrial plants. Initially, the marine realm served to mitigate climate change, but over time, excess accumulated CO2 has disrupted a long-established system of environmental checks and balances.

You see, in oceans, all of that dissolved carbon dioxide interacts with carbonic acid, bicarbonate, and carbonate. This leads to a decrease in overall pH making them less basic. Readers who maintain aquariums likely know that monitoring pH is important for the well-being of the critters inside. The same goes for oceans.

Over the last 250 years, surface pH has decreased by approximately 0.1, but this was a gradual process so marine organisms had the chance to adapt. However, since the upstart of the industrial revolution, pH has been decreasing more rapidly leaving little time for animals to adjust. As a result, we’re already observing deleterious effects on the survival and behavior of some species. Additionally, increased acidity leads to reduced calcification and enhanced dissolution, meaning that corals, coccolithophores, algae, pteropods and more may be in trouble.

While science cannot predict the full ecological consequences of acidification, be assured that the oceans–already under a great deal of pressure–are more vulnerable than ever. And it’s especially important to remember that the plants and animals immediately impacted are not isolated in a closed system. When one part of the biosphere shifts, trophic cascades lead to the disruption all sorts of interactions and this imbalance eventually trickles up to us.

The take home message: What we don’t know, don’t understand, and often ignore can hurt us, so we’d better start paying attention to ocean acidification. Please help spread the word.